MSP430FR6043: ADC waveform problem

Part Number: MSP430FR6043
Other Parts Discussed in Thread: MSP430FR6047

Hi Team,

Good day! I need your help to check our customer's concer as shown below. I have posted it here in behalf of the customer.

I AM USING MSP430FR6043 , FOR WATER FLOWMETER. PIPE DIAMETER 25MM. I AM GETTING PROBLEM WITH ADC CAPTURE WAVEFORM.

attaching ultrasonic sensor datasheet for your reference...i am using MSP430FR6043 with customized PCB, circuit designed as per MSP430fr6043 datasheet.
Evalution software loaded in this PCB...

Water Meter Waveform Sample 1 (1).pdfPSC1.0M014085H2AD2-B0-EN-31(N)_EurekaSmall (1).doc

now adc capture waveform is showing some offset , and actual flow result is fluctuating from max value and then negative value as shown in waveform in water meter sample1 . pdf,

can you guide me , what will be the problem?

Thank you for your support. 

Best regards,

Jonathan